This Prezi on Number Systems by Petra Marjai illustrates the power of Prezi to present and explore concepts that are more difficult to convey with a traditional slide presentation.
YouTube provides a number of resources for teachers to help them make the most of YouTube in the classroom. Use the playlist feature to build collections of videos for your classroom. The community features allow you to easily share content, playlists, and ideas with other YouTube teachers.
This presentation has a number of good ideas and examples for how to use Google Apps for Education. A nice introduction with plenty of "goodies" for more experienced users.
This short video would be excellent for prompting discussion or student research for 6-8 grade science students. Be sure to check out the other great short videos from the "Its Okay to be Smart" YouTube channel as well. Remember, students are not currently able to access YouTube from their devices, so you will need to project this video for the class if you want to use it.